An escalator system comprises a handrail system moving in correspondence with steps of the escalator. The handrail system comprises fixed balustrades and a handrail band with a moving path controlled by a handrail band rail fixed on the balustrades. The handrail band is guided and tensioned by a drive device for the handrail band disposed in a lower bed of the escalator, which drives the handrail band to move in cycle without breaking away from the handrail band rail.
The drive device for the handrail band comprises a driving wheel, a driven wheel, a handrail band drive wheel connected with the driven wheel coaxially, and a handrail band drive chain connected between the drive wheel and the driven wheel in circle. The driving wheel is driven to rotate by a motor, and the handrail band drive wheel, connected with the driven wheel coaxially, is rotated by the handrail band drive chain connected between the driving wheel and the driven wheel in circle. The handrail band extends through a gap between the handrail band drive wheel and a guiding roll for the handrail band, and is pressed against the handrail band drive wheel, so as to be driven to move in circle by a friction force between the handrail band and the handrail band drive wheel.
A problem exists in the drive device for the handrail band of the prior art is, the handrail band drive chain will loosen after running several months, and a pivot point of the handrail band drive wheel needs to be moved far away from the driving wheel to a new pivot point position so as to tension the handrail band drive chain. Furthermore, a pivot point of the guiding roll for the handrail band needs to be adjusted accordingly with the new pivot point position of the handrail band drive wheel, which brings a heavy work on site periodically, and hence a quality problem to the handrail system.
Therefore there exists a need to improve a handrail system in the prior art, especially a handrail band drive device, so as to eliminate or alleviate heavy work on site periodically for the handrail band drive device, and improve quality of the handrail system.